SOOO, I headed up to TorquFreaks today to get some tuning in and see what the motor produces and I was somewhat dissapointed with the results and I wanted to see what you guys thought might be a culprit for low overall horespower numbers, but mean torque?:\

A/F was pretty flat, 13.2-13.5 across the board, we advanced timing, no gains, retarded it, no gains....pull fuel didnt help, added fuel didnt help. I DID pull 157hp once with the a/f at the last 500 rpm being 13.7:1 in which my tuner thought was risky so we brought it down to and ended up with a final tune of 154.93hp/123.39tq

Dyno graph:


Setup:
B18b, 81.5mm, balanced blueprinted
JE 11.5:1 ITR Pistons (10.9:1 static in b18b)
Eagle H-Beam Connecting Rods
Cometic 3-Layer Headgasket
ARP Head Studs
Golden Eagle Block Guard
'92 B18A head
Full Race Port and Polish
3-Angle Valve Job
Crower 404 Camshafts
Crower Dual Valve Springs
Stock Valves and keepers
AEM Adj. Cam gears (Intake+4, exhaust 0)
Hondata s200 w/3step and datalogging
Walbro 255 LPH In-tank Pump
AEM Fuel Rail
B&M Adj. FPR (set at 35psi, no vacuum)
Marshall Fuel Pressure gauge
Blox Intake Manifold
JDM ITR 64mm Throttle body (no FITV or IACV)
Iceman Short Ram Intake
98 GSR Tranny
Quaife Limited Slip Diff
ACT ProLite 8.8lb Flywheel
Exedy Organic Racing CLutch
Pro 1 Top Speed 4-1 SS Header-2" collector
Mozart Cat-Back 2 3/8" (Custom modified)
Straight Pipe

What do you guys think??

PLEASE dont tell me to go LS/VTEC, or I coulda got more power with other options, thanks!

 

What are the primary sizes on your header? 2-inch collector is kinda weaksauce and you might have a bottleneck with that header if your head and cams flow as much air as it seems they do.

 

well from your dyno chart it looks like it stops making power from 6.5K-7K rpm's, so maybe the header is choking your engine up top.

 

ya id be willing to say the 2" collector is strangling ur motor up top

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drchulo &raquo;</TD></TR><TR><TD CLASS="quote">well from your dyno chart it looks like it stops making power from 6.5K-7K rpm's, so maybe the header is choking your engine up top. </TD></TR></TABLE>

You do see the peak at 7700rpm, right?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DAmn &raquo;</TD></TR><TR><TD CLASS="quote">ya id be willing to say the 2" collector is strangling ur motor up top</TD></TR></TABLE>
contact user SMSP about a header for that thing...i would not be surprised if you saw double digit gains all over the place by simply running a top-notch header. Why the +4 on the intake cam?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JohnnyWash1 &raquo;</TD></TR><TR><TD CLASS="quote">You do see the peak at 7700rpm, right?</TD></TR></TABLE>

look at torque, not HP. That's what shows how its losing its ability to breath at higher rpms.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by StyleTEG &raquo;</TD></TR><TR><TD CLASS="quote">

look at torque, not HP. That's what shows how its losing its ability to breath at higher rpms.</TD></TR></TABLE>
huh? That makes no sense...all of the following graphs lose torque fast and hp shoots up and doesn't stop for some time vs. when the torque apex occurred. Please explain

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by StyleTEG &raquo;</TD></TR><TR><TD CLASS="quote">

look at torque, not HP. That's what shows how its losing its ability to breath at higher rpms.</TD></TR></TABLE>


Wrong, try again.

 

You need vtec

 

id say a bigger header can do better, maybe even some more compression. i had some b16 pistons in an LS milled .040" Untuned, i put down 161.2/118.2.
also, i would say you could get some better overall tuning throughout the powerband.especially between 45-55 and 57-63; hell, id even say do some more toggling from 73-83. if your motor was assembled right, you can definately rev higher than 76. I took mine to 82 and it didnt stop pulling power, but i was hesitant as it was untuned.
(never got to tune it, but i heard its making some nice power now)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JohnnyWash1 &raquo;</TD></TR><TR><TD CLASS="quote">Wrong, try again.</TD></TR></TABLE>

actually no...

horsepower is just a measurement of torque over time, if you actually understood this fully you would see exactly what I am saying.

HP = Torque X RPM / 5252

So the amount of torque an engine is creating is directly proportional to how much air it is inducting, and burning. (With slight variations due to burn efficiency and whatnot).

So if the torque is dropping off, that means the engine is not as volumetric effiecent as it was at peak torque. It still makes HORSEPOWER because it is making that amount of torque much quicker than it was previously.

Ever wonder why when people talk about your powerband its only in reference to torque? Notice how his powerband is from 5.5k - 6.5k (the flatest area of peak torque).

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by StyleTEG &raquo;</TD></TR><TR><TD CLASS="quote">


So the amount of torque an engine is creating is directly proportional to how much air it is inducting, and burning. (With slight variations due to burn efficiency and whatnot).

So if the torque is dropping off, that means the engine is not as volumetric effiecent as it was at peak torque. It still makes HORSEPOWER because it is making that amount of torque much quicker than it was previously.

Ever wonder why when people talk about your powerband its only in reference to torque? Notice how his powerband is from 5.5k - 6.5k (the flatest area of peak torque).

</TD></TR></TABLE>

I don't quite totally understand what you are trying to say, could you elaborate more and explain a bit more clearly? Thanks, just wanna learn a few things today

 

Kinda a broad subject, but I will try and be as clear as possible

Basicly the engine is an air pump, it mixes air and fuel and burns them to create heat. The heat is then used as energy to create torque which then moves the car.

So the amount of torque you are creating is proportional to the amount of air entering the cylinders and being burned (since we can easily add more fuel of course, and again ignoring details such as burn efficency). This is often refered to as volumetric efficiency. 100% VE means the cylinders are filled with as much air as possible, where over 100% VE means you have positive pressure (ie Forced induction, or highly efficent NA motors often done through harmonic amplification).

So peak torque is going to occur when you more or less have the most amount VE out of your rpm band.

Now horsepower what everyone focus' on, is a measurement of torque over time. HP might still be going up as torque goes down, but thats because each cylinder is firing much more often at 9,000 rpm vs 5,000 rpm.

 

Hmm, i hope i dont sound like an idiot but im a little bit confused. Now you say that torque is proportional to the amount of air entering the cylinder, etc, etc. But what i dont get is why is it that your torque continues to decrease while power continues to increase. Maybe im not making myself clear enough but i dont get how you said that the engine isn't properly breathing pass 6.5k. When looking at other dyno curves, torque is always decreasing but i have never heard them say that their engine isn't properly breathing in that range. Lol, im confusing myself. please solve this dilema for me.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JohnnyWash1 &raquo;</TD></TR><TR><TD CLASS="quote">

You do see the peak at 7700rpm, right?
</TD></TR></TABLE>Yes it does peak at 7700, but from 7K rpms and on it pretty much just flattens out...so there maybe something holding the engine back from getting more power. It could be the header...

 

Well as you rev higher it becomes increasingly harder to get air to fill the cylinders, there are a lot of things that fight it and in many cases its at a sacrifice of lower end. Most people either don't realize that their engine is running out of breath at high end, or they accept it as a means of having some low end.

The b16 is a perfect example, very short stroke. The result is almost no low end torque (partially due to displacement), but due to the amount of time that the pistons dwell at TDC compaired to the B18C's and B's they are able to fill the cylinders more efficently at higher rpm.

The reson that HP still goes up is because how it is measured from torque.

HP = Torque * RPM / 5252

So if your making 150 lbs/ft at 6,000 , 140lbs/ft at 7,000 and 125lbs/ft at 8,000 you are still making

6,000 - 171whp
7,000 - 186whp
8,000 - 190whp

Power is still going up even though torque is dropping dramaticly.

If you look at all the dyno graph's you posted towards the higher rpm they all lose about 25 or more lbs/ft of torque


In reference to the poster, if he were able to flaten his torque curve out and make 120ft/lbs of torque at 7,500 rpm it would result in 171whp

 

very well said bro.

 

People seem to overlook the importance of the tq curve. It can tell you ALOT about how your engine is/isnt performing

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sukii &raquo;</TD></TR><TR><TD CLASS="quote">Hmm, i hope i dont sound like an idiot but im a little bit confused. Now you say that torque is proportional to the amount of air entering the cylinder, etc, etc. But what i dont get is why is it that your torque continues to decrease while power continues to increase. Maybe im not making myself clear enough but i dont get how you said that the engine isn't properly breathing pass 6.5k. When looking at other dyno curves, torque is always decreasing but i have never heard them say that their engine isn't properly breathing in that range. Lol, im confusing myself. please solve this dilema for me.</TD></TR></TABLE>

At higher RPM's, you have what is called overlap. This simply means that the cams are rotating so fast the the intake and exhaust valves will be open at the same time(not the whole time...just briefly). This causes air coming from the intake to go straight out the exhaust....not all but some. This reduces VE by not allowing as much air to fill the cylinders as it did at lower rpms(no overlap). And no you dont sound like an idiot...everyone has to learn sometime

I hope this makes sense...i just got off of work and im beat. normally i wouldve taken a little more time to explain it in detail.

 

ahh, i c, that makes a lot more sense. But im just curious how you guys were able to come upwith the assumption that the engine is not breathing properly in the upper rpm's based on the torque curve. I mean im looking at the other torque curves as wel lfrom the other graphs and they all seem to dip even faster than the one he just showed us. Could you clear this up for me? Thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by StyleTEG &raquo;</TD></TR><TR><TD CLASS="quote">

actually no...

horsepower is just a measurement of torque over time, if you actually understood this fully you would see exactly what I am saying.

HP = Torque X RPM / 5252

So the amount of torque an engine is creating is directly proportional to how much air it is inducting, and burning. (With slight variations due to burn efficiency and whatnot).

So if the torque is dropping off, that means the engine is not as volumetric effiecent as it was at peak torque. It still makes HORSEPOWER because it is making that amount of torque much quicker than it was previously.

Ever wonder why when people talk about your powerband its only in reference to torque? Notice how his powerband is from 5.5k - 6.5k (the flatest area of peak torque).

</TD></TR></TABLE>

You are correct; I wasn't trying to argue that point. VE goes down with RPMS no matter what---have you ever read how terribly inefficient F1 cars are at 19K rpm? I thought you were referencing the general decline of torque at higher rpms....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JohnnyWash1 &raquo;</TD></TR><TR><TD CLASS="quote">

VE goes down with RPMS no matter what---..</TD></TR></TABLE>

That is not a correct statement to say either. If this were the case cars would make peak torque at 0rpm, which we all no is not happening. The design of the system (ie. the engine) will determine the VE of the motor at various engine speeds. VE will be poor at low engine speeds and increase to a peak at which point it will drop, above that peak VE will continue to drop unless something changes to alter the motors volumetric effeciency, such as VTEC or VVTL.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JohnnyWash1 &raquo;</TD></TR><TR><TD CLASS="quote">

You are correct; I wasn't trying to argue that point. VE goes down with RPMS no matter what---have you ever read how terribly inefficient F1 cars are at 19K rpm? I thought you were referencing the general decline of torque at higher rpms....</TD></TR></TABLE>
i agree, it's a fact of life VE goes down as RPM goes up after the torque peak...

Yet, I am still stuck on styleTEG's statement; his explanations didn't help me at all regarding his orig. statement and this guy's low HP peak....i still don't understand how looking at the torque is going to report poor high RPM breathing...every setup loses torque as VE goes down, and hp then goes up...I would look at flat portion at the end of the hp plot and determine it probably has a breathing issue; either too much advance on the cams, restrictive in-out...something. The torque curve looks fine to me.

If you showed those graphs i posted, w/o the HP plot, can you explain to me why those are any different from this guys TQ plot in terms of high-rpm breathing?

Like, this guy's graph shows that HP really starts to pick up as soon as the tq plot hit its apex...


the tq curve on nicklk's setup starts a rapid decent at 6.5, and ideally the HP should shoot up from there...but it doesnt...indicating an issue. i would not know that without looking at the hp graph




Modified by 337 GTI 1.8t at 7:42 PM 6/17/2005

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BryanPendleton &raquo;</TD></TR><TR><TD CLASS="quote">

That is not a correct statement to say either. If this were the case cars would make peak torque at 0rpm, which we all no is not happening. The design of the system (ie. the engine) will determine the VE of the motor at various engine speeds. VE will be poor at low engine speeds and increase to a peak at which point it will drop, above that peak VE will continue to drop unless something changes to alter the motors volumetric effeciency, such as VTEC or VVTL.

</TD></TR></TABLE>

i would assume johnnywash meant VE drops as rpm increases after the torque peak....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">
Yet, I am still stuck on styleTEG's statement; his explanations didn't help me at all regarding his orig. statement and this guy's low HP peak....i still don't understand how looking at the torque is going to report poor high RPM breathing
</TD></TR></TABLE>

Again.... the amount of torque created is directly related to the amount of air the motor is breathing. (Again overlooking burn efficency whatnot).

Horsepower is just a measure of torque. So when you say you are looking at the HP curve and see if it flatens, you are really just looking at a different measure of torque.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">
.every setup loses torque as VE goes down, and hp then goes up...
</TD></TR></TABLE>

hp goes up with RPM, not as VE goes down. Look at the formula again, and try some numbers out. My example showed perfectly that if he were able to flaten his torque out how it would increase his peak numbers.

How would you increase torque in the higher rpm's? Increase the motors breathing ability.

You can easily see that his current engine package favors peak volumetric effiecency in the midrange, not in the high end. With a larger collector, peak torque will occur later.

As far as VE dropping as RPM's increase, that is not some much of a rule as a pattern. It becomes harder to get better VE as RPM's increase, but its not a downward scale of any sorts.